We have a direct statement in the episode that the pressure gets greater as you descend towards the centre of the sphere. However, when the Delta Flyer gets a puncture at the core of the ocean the water just dribbles in, whereas it should have been a high pressure jet.

Great Moment :

The first sight of the space ocean.

Body Count :

Only Paris's rank.

Factoid :

Amazingly, the volume of water stated for the ocean is about right for a class M world.

Plotline

The episode opens with Paris being reduced in rank and thrown into the Brig for thirty days. As he dictates a letter to his father, we learn the reason; when Voyager encountered a huge sphere of water floating in space, they offer its residents help in repairing the ancient machine which controls the unique environment. But when the locals decline their help, Paris decides to take matters into his own hands.